Many physical phenomena and industrial applications involve multiphase fluid flows and hence it is of high importance to be able to simulate various aspects of these flows accurately. The Dynamic Contact Angles (DCA) and the contact lines at the wall boundaries are a couple of such important aspects. In the past few decades, many mathematical models were developed for predicting the contact angles of the inter-face with the wall boundary under various flow conditions. These models are used to incorporate the physics of DCA and contact line motion in numerical simulations using various interface capturing/tracking techniques. In the current thesis, a simple approach to incorporate the static and dynamic contact angle boundary conditions using the level set method is developed and implemented in multiphase CFD codes, LIT (Level set Interface Tracking) (Herrmann (2008)) and NGA (flow solver) (Desjardins et al (2008)). Various DCA models and associated boundary conditions are reviewed. In addition, numerical aspects such as the occurrence of a stress singularity at the contact lines and grid convergence of macroscopic interface shape are dealt with in the context of the level set approach.
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机译：许多物理现象和工业应用都涉及多相流体流动，因此，能够准确模拟这些流动的各个方面非常重要。动态接触角（DCA）和墙边界处的接触线就是其中几个重要方面。在过去的几十年中，开发了许多数学模型来预测在各种流动条件下界面与壁边界的接触角。这些模型用于通过各种接口捕获/跟踪技术将DCA物理原理和接触线运动纳入数值模拟中。在当前的论文中，开发了一种简单的方法来使用水平集方法结合静态和动态接触角边界条件，并在多相CFD代码，LIT（水平集接口跟踪）（Herrmann（2008））和NGA（流量求解器）中实现（Desjardins et al（2008））。审查了各种DCA模型和相关的边界条件。另外，在水平集方法的背景下，处理数值方面，例如在接触线上出现应力奇异性和宏观界面形状的网格收敛。
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